The Role Of Iodine In The Body

Iodine is a chemical element required for good health, as it has several roles in the body. Iodine is needed to make thyroid hormones and promote a healthy pregnancy, as well as to prevent a number of conditions. Because foods don't naturally contain much iodine, salt is fortified with iodine. It's estimated that iodized salt is used regularly by about half the U.S. population, according to MedlinePlus.

Thyroid Function

The thyroid gland can't function without iodine because it's needed to make thyroid hormones. Insufficient iodine can cause an enlarged thyroid gland. This unsightly swelling in the front of the neck is known as a goiter. Insufficient iodine can also affect thyroid function by causing hypothyroidism, or an underactive thyroid. Symptoms include fatigue, weight gain and depression. Thyroid function is important for fertility, as well. Iodine deficiency leading to low levels of thyroid hormones can cause women to stop ovulating, leading to infertility.

Normal Metabolism

Iodine is needed for the normal metabolism of cells. Metabolism is the process of converting food into energy. Insufficient iodine can slow down the body's metabolism, which can result in weight gain. "Because thyroid hormones regulate metabolism and growth, when production of these hormones is slowed or stopped due to iodine deficiency, your metabolism can become sluggish," notes Beth Reardon, registered dietitian and Director of Nutrition at Duke University Integrative Medicine. The metabolic rate determines how fast calories are burned. A higher metabolic rate is thought to speed up weight loss.

Healthy Pregnancy

Iodine plays a crucial role in promoting a healthy pregnancy. Iodine deficiency during pregnancy can cause high blood pressure in the mother and mental retardation in the baby. In extreme cases, iodine deficiency during pregnancy can cause the baby to be born with a disorder that involves severely stunted physical and mental growth. The Linus Pauling Institute indicates that iodine deficiency during pregnancy may also increase the risk of miscarriage, stillbirth and birth defects.

Other Roles

Other possible iodine roles include prevention of cancer. According to Medline Plus, iodine deficiency might increase the risk of prostate, breast, endometrial, ovarian and thyroid cancer. Help with the breast lumpiness and discomfort associated with fibrocystic breasts is another potential benefit of getting enough iodine, according to the Linus Pauling Institute. The good news is that iodine deficiencies are rare in the United States due to iodized salt. Fish, especially haddock, mackerel and cod, are the best natural sources of iodine, adds Reardon. Supplements are available for people who don't get enough iodine from iodized salt and food.